Congreso Internacional del Agua – Termalismo y Calidad de Vida. Campus da Auga, Ourense, Spain, 2017.

1

Abstract This study aims to present the importance of the groundwater inventories mapping in urban areas. In order to achieve that goal, a GIS multi-technique approach using hydroclimatology, geology, morphotectonics, hydrogeology, historical geography, remote sensing and land-use, was performed to assess groundwater systems in Amarante urban area (NW Portugal).

1 Introduction

Nowadays, living in a populated urban area is a worldwide trend. According to UN-Habitat [1] more than 50% of the population currently live in urban areas, with that number increasing to around 70% in Europe alone. Such a high percentage of people living in cities means more environmental contamination and/or pollution, due to high consumption of energy and raw materials (Marsalek et al. [2]).

Human activities in urban areas necessarily changed the natural water cycle. For that reason, is more correctly in this areas comprehend the so-called urban water cycle. Water inventories are a fundamental tool in order to assess the connectivity and interdependence between human activities and sustainable water resources (Marsalek et al. [2]). In addition, the factors such as climate, geology, geomorphology and land-use are also crucial for the study and understanding of the urban water cycle (e.g., Sherlock [3], Leopold [4] Leggett [5], Ehlen et al. [6], Wilkinson [7], Afonso et al. [8]).

However, human activities such as land-use are an even stronger influence on terrestrial hydrology than climate and its changes (Taylor et al. [9]). Moreover, there is a need to provide the population with safe water, sanitation and drainage systems, which are themselves fundamental for the understanding and management of groundwater resources in an urban context (Rietveld et al. [10]).

The challenge in the studying of integrated sustainable water resources management is not only scientific, but also technical, socio-economic, and also in heritage, cultural and ethical dimensions (e.g., Bahri [11], UNESCO [12], Braga et al. [13], Sharp and Hibbs [14], Schirmer et al. [15], Foster et al. [16], Chaminé [17]).

Climate changes associated to the increasing of the urban population address an enormous pressure on groundwater resources. Because that an integrated multidisciplinary approach is required. Acquiring data in urban areas is sometimes rather difficult and the mapping plays a central role in urban geoscience. In that approach urban geoscience needs to evolve to a new paradigm of a smart urban geoscience, particularly related to in situ geotechnical investigations, ground modelling, urban hydrology, geological resources, heritage and geohazard assessments, and planning purposes (Chaminé et al. [18, 19]; Freitas et al. [20]).

The Amarante urban area, NW Portugal, was chosen to illustrate that approach. This work results mainly from the surveys to develop the “geotechnical map of the Amarante city” (in progress by the Laboratory of Cartography and Applied Geology, ISEP|P.Porto).

Groundwater mapping techniques in urban areas: an example from Amarante city (NW Portugal)

L. Freitas, S. Gomes Laboratory of Cartography and Applied Geology, School of Engineering (ISEP), Polytechnic of Porto, Porto, Portugal.

H.I. Chaminé Laboratory of Cartography and Applied Geology, Department of Geotechnical Engineering, School of Engineering (ISEP), Polytechnic of Porto, Porto, Portugal; Centre GeoBioTec|UA, Portugal.

Keywords: Hydrogeological mapping, Urban groundwater, Water Resources, NW Portugal.

Congreso Internacional del Agua – Termalismo y Calidad de Vida. Campus da Auga, Ourense, Spain, 2017.

2

Amarante is located in the eastern part of the district of Porto and is also its largest municipality, with an area of approximately 301.3 km2 (INE [21]), divided into 26 parishes, and 55.171 inhabitants (INE [21]). The studies performed in Amarante city can contribute to the guidelines for the planning and management of water resources in an equitable, sustainable and ethical manner.

For the development of this study a multidisciplinary methodology was applied, namely hydroclimatology, geology, morphotectonics, hydrogeology, historical geography, remote sensing and land-use. Field and desk techniques for hydrogeological mapping and surface geological fieldwork have been applied, and cartographic issues were developed through the application of GIS based tools (e.g., Struckmeier and Margat [22], Zaporozec [23], Witkowski et al. [24], Howard [25], Assaad et al. [26], Teixeira et al. [27], and references therein).

2 Urban hydrogeological mapping

The study consists of the compilation, revision and systematization of the hydroclimatological, geological, geomorphological and hydrogeological information, as well as the data gathered in the fieldwork in the Amarante urban area during 2015/2016. A geographical database was created in a GIS environment, enabling the systematization of data in the form of cartography. This inventory was supported by extensive cross-checking and analysis of historical sources and related to previous mapping.

A preliminary hydrogeological inventory was carried out in the Amarante urban area (Gomes [28]). Figure 1 presents several aspects of the developed hydrogeological inventory. In addition, an alphanumeric database ("Cart-Geot|AMAR") was designed in this study (Figure 2). The database permitted the management of the central information and the connection to a GIS platform. This connection enables a spatial and geographical representation of fundamental mapping data, as well as to obtain several thematic maps or key mapping outputs.

In the present area of study, 26 points of water were inventoried: 14 fountains; 5 water mines; 4 water tanks; 2 washing places and 1 well (Figure 3). “In situ” measurements covered 14 water points; 9 fountains, 4 water tanks and 1 washing place. The temperature of these waters has a median value of 20.4ºC. These waters are slightly acidic with a median pH value of 5.18 (pH values ranged from 5.2

to 7.2). Electrical conductivity measurements mainly ranged from 130 to 490 µS/cm, which indicate the presence of medium mineralised waters.

Figure 1. Several aspects of the fieldwork campaigns (Amarante

urban area): Georeferencing fountains and public washing places

(a, b, d); locating a water mine (c); measuring the flow (e);

measuring temperature, pH and electrical conductivity in a

fountain (f).

Figure 2. Hydrogeological field inventory datasheet: an example of the database “Cart-Geot|AMAR”.

Congreso Internacional del Agua – Termalismo y Calidad de Vida. Campus da Auga, Ourense, Spain, 2017.

3

Figure 3. Amarante urban hydrogeological inventory (adapted from Gomes [28] and LABCARGA archives).

3 Concluding remarks

This work highlights the importance of GIS urban groundwater mapping as a valuable tool to contribute to a balanced urban planning management aiming a sustainable design with nature, environment, heritage and society. In order to plan and assess water supply safety, as well as for reasons of investment strategy, it is vital to develop these types of inventories in urban areas, regarding a better use of their groundwater resources. In this approach, urban groundwater studies assume a major significance contributing to an integrated sustainable management.

Acknowledgments

This work was supported by the framework of the Laboratory of Cartography and Applied Geology (re-equipment program IPP-ISEP|PAD’2007/08).

References [1] UN-Habitat [United Nations Human Settlements

Programme]. State of the world’s cities 2012/2013: prosperity of cities. United Nations Human Settlements Programme, World Urban Forum edition, 2012.

[2] Marsalek, J., Jiménez-Cisneros, B., Karamouz, M., Malmquist, P.A., Goldenfum, J., Chocat, B. Urban water cycle processes and interactions. UNESCO‐HP Urban water series. Taylor & Francis, Netherlands, 2008.

[3] Sherlock, L.R. Man as a geological agent: an account of his action on inanimate nature. H.F. & G. Witherby, London, 1922.

[4] Leopold, L. Hydrology for urban land planning: a guidebook on the hydrologic effects of urban land use. United States Geological Survey Circular 554, USGS, Reston, 1968.

[5] Leggett, R.F. Cities and geology. McGraw‐Hill, New York, 1973.

[6] Ehlen, J., Haneberg, W.C., Larson, R.A. Humans as geologic agents. Reviews in Engineering Geology. The Geological Society of America, Volume XVI, Boulder, Colorado, 2005.

[7] Wilkinson, B.H. Humans as geologic agents: a deep-time perspective. Geology, 33(3):161-164, 2005.

[8] Afonso M.J., Freitas L., Pereira A.J.S.C., Neves L.J.P.F., Guimarães L., Guilhermino L., Mayer B., Rocha F., Marques J.M. & Chaminé H.I. Environmental groundwater vulnerability assessment in urban water mines (Porto, NW Portugal). Water, 8(11):499, 2016.

[9] Taylor, R.G., Scanlon, B., Döll, P., Rodell, M., van Beek, R., Wada, Y., Longuevergne, L., Leblanc, M., Famiglietti, J.S., Edmunds, M., Konikow, L., Green, T.R., Chen, J., Taniguchi, M., Bierkens, M.F.P., MacDonald, A., Fan, Y., Maxwell, R.M., Yechieli, Y., Gurdak, J.J., Allen, D.M., Shamsudduha, M., Hiscock, K., Yeh, P.J.F., Holman, I., Treidel, H. Ground water and climate change. Nature Climate Change, 3:322-329, 2013.

[10] Rietveld, L.C. Siri, J.G., Chakravarty, I., Arsénio A.M., Biswas R. & Chatterjee A. Improving health in cities through systems approaches for urban water management. Environmental Health, 15(Suppl 1):S31, 2016.

[11] Bahri, A. Global integrated urban water management. Global Water Partnership, Technical Committee background papers no. 16, 2012.

[12] UNESCO. International Hydrological Programme (IHP) eighth phase “water security: responses to local, regional, and global challenges” strategic plan IHP-VIII (2014-2021), 2012.

Congreso Internacional del Agua – Termalismo y Calidad de Vida. Campus da Auga, Ourense, Spain, 2017.

4

[13] Braga, B., Chartres, C., Cosgrove, W.J., Veiga da Cunha, L., Gleick, L., Kabat, P., Ait Kadi, M., Loucks, D.P., Lundqvist, J., Narain, S., Xia, J. Water and the future of humanity: revising water security. Gulbenkian Think Tank on Water and the Future of Humanity. Calouste Gulbenkian Foundation, Lisbon; Springer, New York, 2014.

[14] Sharp, J.M. & Hibbs, B. Special issue on hydrogeological impacts of urbanization. Environmental & Engineering Geoscience, 18(1), 2012.

[15] Schirmer, M., Leschik, S. & Musolff, A. Current research in urban hydrogeology: a review. Advances in Water Resources, 51: 280-291, 2013.

[16] Foster, S., Hirata, R. & Howard, K. Groundwater use in developing cities: policy issues arising from current trends. Hydrogeology Journal, 19: 271-274, 2011.

[17] Chaminé H.I. Water resources meet sustainability: new trends in environmental hydrogeology and groundwater engineering. Environmental Earth Sciences, 73(6):2513-2520, 2015

[18] Chaminé, H.I., Afonso, M.J., Freitas, L. From historical hydrogeological inventory through GIS mapping to problem solving in urban groundwater systems. European Geologist Journal, 38:33-39, 2014.

[19] Chaminé H.I., Teixeira J., Freitas L., Pires A., Silva R.S., Pinho T., Monteiro R., Costa A.L., Abreu T., Trigo J.F., Afonso M.J. & Carvalho J.M. From engineering geosciences mapping towards sustainable urban planning. European Geologist Journal, 41:16-25, 2016.

[20] Freitas L., Pereira A.J.S.C., Afonso M.J. & Chaminé H.I. Urban groundwater mapping techniques: importance on urban water cycle. In: J.M. Faílde, A. Formella, J.A. Fraiz, M. Gómez-Gesteira, F. Pérez, V.R. Vázquez (eds.), Proceedings Ist International Congress on Water Healing Spa and Quality of Life / I Congreso Internacional del Auga, Termalismo y Calidad de Vida (Ourense, Spain, 23-24 September 2015), Campus da Auga, Vicerrectoría del Campus de Ourense, Universidade de Vigo, p. 145-150, 2016.

[21] INE – Instituto Nacional de Estatística. Informação estatística sobre a população portuguesa: Concelho de Amarante, 2013. (consultado em Março de 2016)

[22] Struckmeier, W.F. & Margat, J. Hydrogeological maps: a guide and a standard legend. International Association of Hydrogeologists, Hannover, volume 17, 1995.

[23] Zaporozec, A. Groundwater contamination inventory: a methodological guide with a model legend for groundwater contamination inventory and risk maps. UNESCO, Paris, 2004.

[24] Witkowski, A.J., Kowalczyk, A. & Vrba, J. Groundwater vulnerability assessment and mapping. IAH Selected Papers on Hydrogeology. Taylor & Francis Group, London, volume 11, 2007.

[25] Howard, K. Urban groundwater: meeting the challenge. IAH Selected Papers on Hydrogeology. Taylor & Francis Group, London, volume 8, 2007.

[26] Assaad, F.A., LaMoreaux, P.E., Hughes, T. Field methods for geologists and hydrogeologists. Springer-Verlag, Berlin, 2004.

[27] Teixeira, J., Chaminé, H.I., Carvalho, J.M., Augusto Pérez-Alberti, Fernando Rocha. Hydrogeomorphological mapping as a tool in groundwater exploration. Journal of Maps, 9(2):263–273, 2013.

[28] Gomes S. Geotecnia urbana de Amarante: estudos preliminares para uma cartografia geotécnica. Instituto Superior de Engenharia do Porto (Dissertação de Mestrado), 2016.